JEE-MAIN SERIES Chemistry
Thermochemistry
7 previous year questions.
Volume: 7 Ques
Yield: Medium
High-Yield Trend
4
2026 2
2025 1
2023 Chapter Questions 7 MCQs
01
PYQ 2023
easy
chemistry ID: jee-main
Solid fuel used in rocket is a mixture of Fe₂O₃ and Al (in ratio 1 : 2) the heat evolved (KJ) per gram of the mixture is ______ (Nearest integer)
Given
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Given
}
02
PYQ 2025
medium
chemistry ID: jee-main
Total enthalpy change for freezing of 1 mol water at 10°C to ice at -10°C is ______ (Given: , , and )
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03
PYQ 2025
medium
chemistry ID: jee-main
Consider the following data: - Heat of formation of = -393.5 kJ mol
- Heat of formation of = -286.0 kJ mol
- Heat of combustion of benzene = -3267.0 kJ mol The heat of formation of benzene is ________________________ kJ mol (Nearest integer).
04
PYQ 2026
medium
chemistry ID: jee-main
Gas ‘A’ undergoes change from state ‘X’ to state ‘Y’. In this process, the heat absorbed and work done by the gas is 10 J and 18 J respectively. Now gas is brought back to state ‘X’ by another process during which 6 J of heat is evolved. In the reverse process of ‘Y’ to ‘X’, the work done is:
1
18 J of the work is done by the gas ‘A’.
2
2 J of the work is done by the gas ‘A’.
3
12 J of the work is done on the gas ‘A’ by the surrounding.
4
14 J of the work is done on the gas ‘A’ by the surrounding.
05
PYQ 2026
medium
chemistry ID: jee-main
Consider the following equations: (i)
(ii)
(iii)
(iv)
The enthalpy of formation of anhydrous solid is:
1
kJ mol
2
kJ mol
3
kJ mol
4
kJ mol
06
PYQ 2026
hard
chemistry ID: jee-main
If the enthalpy of sublimation of Li is , enthalpy of dissociation of is , ionization enthalpy of Li is , electron gain enthalpy of F is , and standard enthalpy of formation of LiF is , then the magnitude of lattice enthalpy of LiF is ____________ kJ mol (Nearest integer).
07
PYQ 2026
medium
chemistry ID: jee-main
Consider the following data :
Enthalpy of sublimation of graphite
Dissociation enthalpy of
The bond enthalpy of C-H bond is given by :}
Enthalpy of sublimation of graphite
Dissociation enthalpy of
The bond enthalpy of C-H bond is given by :}
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